Whalatane
2 weeks ago
Hello Nephrology article yesterday
Phosphate binder rule is disease-specific discrimination
Add topic to email alerts
In April, CMS issued guidance for the inclusion of oral-only drugs in the end-stage renal disease bundled payment. The directive included Xphozah as a renal dialysis service.
Xphozah, (tenapanor, Ardelyx) is a first-in-class phosphate absorption inhibitor approved to lower serum phosphorus levels for adults on dialysis. CMS intends to include the agent in the ESRD prospective payment system effective Jan. 1, 2025, but unlike calcimimetics and phosphate binders, tenapanor will have its own transitional drug add-on payment adjustment (TDAPA) and be excluded in the calculation for a permanent add-on payment. Under this guidance, tenapanor will be moved from Medicare Part D to Part B, and Part D pharmacies will no longer be allowed to fill prescriptions to Medicare ESRD beneficiaries.
Premila Bhat, MD, FASN, AHSCP-CHS, and J. Ganesh Bhat, MD, FASN
Tenapanor in phosphate control
Hyperphosphatemia and metabolic bone disease are the most challenging clinical issues facing nephrologists who treat patients on dialysis. Phosphates are ubiquitous in the diet, and normal kidneys excrete most of the phosphates absorbed from the gut. With the decline of kidney function, phosphates accumulate in the blood, leading to secondary hyperparathyroidism and metabolic bone disease.
Since dialysis became a routine procedure for patients with ESRD, traditional management of elevated phosphorus has been through oral drugs that bind phosphates and prevent absorption. Aluminum hydroxide gel and calcium-containing compounds, such as calcium acetate or citrate, were the mainstay for controlling hyperphosphatemia in dialysis. Aluminum toxicity and concerns about calcium burden led to the introduction of other phosphate binders, such as sevelamer carbonate, sevelamer hydrochloride, lanthanum carbonate and iron-based phosphate binders.
Premila Bhat, MD, FASN, AHSCP-CHS
Premila Bhat
J. Ganesh Bhat, MD, FASN
J. Ganesh Bhat
Dietary restriction and dialysis using currently available dialyzer membranes alone are insufficient to maintain phosphate balance; hence, there is a need to bind phosphate in the gut to prevent absorption. Compliance with conventional phosphate binder therapy is difficult and directly attributable to the “pill burden” and need to take the medication with or soon after meals multiple times a day. Gastrointestinal adverse events and intolerance to the binders further complicate the matter.
Many patients on dialysis cannot maintain a serum phosphorus level between 3.5 mg/dL and 5.5 mg/dL even when using medications to manage the condition. The addition of tenapanor as an add-on therapy for patients who have an inadequate response to phosphate binders or intolerance to any dose of phosphate binder would make these goals easier to achieve and prevent complications due to secondary hyperparathyroidism.
Legal action
In July, Ardelyx started legal action arguing that CMS did not have the authority to include oral-only drugs, such as phosphate binders and phosphate absorption inhibitors, in the bundled payment system. From a mechanism-of-action point of view, Ardelyx argued, these drugs should not be labeled as renal dialysis services because the drugs are not administered either orally or parenterally during dialysis treatment, and a parenteral form of phosphate binder or absorption inhibitor is unlikely to be developed.
The judge dismissed the case on Nov. 8. CMS will move the drug from Medicare Part D to Part B as planned on Jan. 1, 2025. Ardelyx has yet to accede to CMS’s request for it to apply for a Healthcare Common Procedure Coding System code and TDAPA status, leaving dialysis providers with no clear pathway to be reimbursed.
CMS stated that moving phosphate binders from Medicare Part D to Part B improves beneficiary access to these medications. Medicare Part D enrollment among patients with ESRD had increased to almost 80% in 2021, and twice as many patients with ESRD qualify for low-income subsidies as those without ESRD. Medicare seeks to improve access to these drugs to all patients with ESRD under Part B, and moving phosphate binders to Part B from Part D would have a negligible impact on access to these drugs. However, this change would burden dialysis providers to procure the drugs be the gatekeeper, keeping an eye on the cost.
Equity in ESRD
ESRD is one of the clearest examples of racial and ethnic disparity in health care in the United States. Black and Latino patients are affected by ESRD four times and 1.3 times more, respectively, than white patients. Furthermore, poverty, as measured by dual eligibility status and low-income subsidies, makes ESRD the poster child for disparity in health care in the country. Since the introduction of the ESRD bundle, CMS has experimented with ineffective ideas, such as TDAPA and transitional add-on payment adjustment for new and innovative equipment and supplies (TPNIES) and mandatory ESRD Treatment Choices model, which have an enormous and often negative impact on the lives of patients with ESRD.
Under the current method used by CMS, innovative drugs and technologies are less attractive to innovators and investors, limiting access of patients with ESRD to the advantage of these drugs and technologies in stark contrast to patients who have cancer or heart disease.
For example, Korsuva (difelikefalin, Cara Therapeutics) is a novel anti-pruritic drug that could have treated severe itching for one of six patients on hemodialysis. After the TDAPA period for the drug ended, CMS adopted a 3-year adjustment that spread the cost of it across all Medicare treatments. To recover the cost of providing the drug to a single patient, a facility would have to treat hundreds of patients who do not require it. No facility has a sufficient patient population to make that equation work. Consequently, only a fraction of patients who would have benefited from the drug are now receiving it, and its future availability remains uncertain.
Under the current bundled payment and drug designation process, CMS has reinforced systematic discrimination against patients with ESRD that the administration has indicated it seeks to end. The current system stifles innovation and puts the financial burden on dialysis providers to bear the full cost of providing these expensive drugs and technologies to patients without adequate reimbursement.
Patients with ESRD are discriminated against with regard to access to novel therapeutics, devices and diagnostics compared with their peers without ESRD. Oncology, cardiology, diabetes and patients with other rare diseases enjoy a rich innovation pipeline due to a reimbursement system that rewards companies for innovating in these therapeutic areas. It is time for Congress and other policymakers to revisit how innovation is sustainably paid for in ESRD to ensure brave patients are not left behind.
For more information:
Premila Bhat, MD, FASN, AHSCP-CHS, is CEO of Tidal Home Dialysis LLC, and a partner at NY Kidney Hypertension Medicine in Ridgewood, New York. She can be reached at pbhat@atlanticdialysis.com.
J. Ganesh Bhat, MD, FASN, is a principal at Atlantic Dialysis Management Services LLC, in College Point, New York. He can be reached at jbhat@atlanticdialysis.com.
Published by:
nephrology news and issues logo
Sources/DisclosuresCollapse
Disclosures: The authors report no relevant financial disclosures.
Kiwi